AB0801 The ASAS Health Index (HI): Construct validity and responsiveness in relation to TNF inhibitor (TNFi) treatment in patients with axial spondyloarthritis (axSpA).
Authors: S. Juhl Pedersen, I. J. Sørensen, B. Jensen, O. Madsen, M. Klarlund, J. Møllenbach Møller, M. P. Johansson, K. K. Gosvig, M. Østergaard
Journal: Annals of the Rheumatic Diseases (2022)

Background The Assessment of Spondyloarthritis International Society (ASAS) has developed the ASAS HI aiming to capture the full range of functioning and disability in patients with axSpA. Objectives To examine the construct validity and responsiveness of ASAS HI in relation to TNFi treatment. Methods In this investigator-initiated 52-week prospective observational study (MANGO study; NCT02011386 )(3) axSpA patients initiated sc. Golimumab 50 mg every month. Key inclusion criteria were BASDAI &gt;4.0 and sacroiliitis on radiography and/or MRI. Results 45 of 53 TNFi naïve patients completed ASAS HI at weeks 0, 4, 16 and 52. 55.6% were male, 75.6% HLA-B27 positive, median age 34.6 yrs (IQR 28.3;46.1) and symptom duration 5.1 yrs. (2;13)(Table 1A). ASAS HI decreased from week 0 to weeks 4, 16 and 52, from median 10.0 (IQR 8;11)) to 7.0 (2.3;10), 5.5 (1.3;8) and 4.0 (1;7.5)(Wilcoxon-Pratt; all p&lt;0.001). Patients with low ASAS HI (score 0-5, good heath state(4)) at week 16 and 52 had significantly lower ASDAS, BASDAI, BASFI, pain, pt. global and CRP than patients with moderate to high ASAS HI (6-17) (Table 1B). Patients with a decrease of &gt;3 (clinically meaningful change(3)) or &gt;30%(5) in ASAS HI from week 0-16 had significantly larger reductions in ASDAS, BASDAI, BASFI, pain, pt. global and SPARCC MRI spine inflammation score (Table 1C). At baseline, ASAS HI correlated with BASFI and SPARCC SIJ inflammation score ( rho : 0.37-0.38, p&lt;0.05), and changes in ASAS HI from week 0-16 correlated with changes in ASDAS, BASDAI, BASFI, pain, pt. global (0.51-0.67, p&lt;0.001) and change in MRI SIJ inflammation score (0.30, p&lt;0.05). ASAS HI had high responsiveness (Table 1D). Table 1. Diseases measures at baseline (Table 1A), stratified according to ASAS HI states at week 16 and 52 (Table 1B), changes from week 0 to 16 and 52 (Table 1C) and responsiveness (Table 1D). Table 1A Table 1B Table 1C Table 1D Baseline ASAS HI at week 16 ASAS HI at week 52 Absolute change in ASAS HI week 0 to 16 Percentage change in ASAS HI week 0 to 16 Responsiveness week 0-16 0-5 6-17 0-5 6-17 &lt;3 ≥3 &lt;30% ≥30% SRM ES n=45 n=22 n=22 n=26 n=16 n=18 n=26 n=16 n=28 n=45 n=45 ASAS HI 10.0 (8;11) 1.5*** (1;4) 8.0 (7;10) 2.0*** (0.8;3.3) 9.5 (7;10.8) -1.5*** (-2;2) -6.0 (-12;-3) -1*** (-2;2) -5.5 (-12;-2) 1.6 1.3 ASDAS 3.7 (3.1;4.2) 1*** (0.9;1.5) 2.1 (1.1;3.1) 1.2*** (0.8;1.5) 2.2 (1.8;3.3) -1.3*** (-2.5;1) -2.2 (-4.6;-1.3) -1.2*** (-2.5;1) -2.2 (-4.6;-1.3) 2.5 1.7 BASDAI 6.1 (5;7.2 0.9*** (0.5;2.3) 3.2 (1.8;5.1) 1.3*** (0.3;2.3) 3.8 (2.9;5.7) -1.7*** (-5.3;0.9) -4.9 (-6.7;-1.9) -1.6*** (-5.3;0.9) -4.8 (-6.7;-1.9) 2.7 1.8 BASFI 4.4 (3;5.9 0.6*** (0.3;1.4) 2.3 (1.4;4) 0.3*** (0.1;1.4) 2.5 (1.5;3.3) -1.2*** (-4.4;1.2) -3.5 (-6.7;-0.2) -1.1*** (-3.9;1.2) -3.5 (-6.7;-0.15) 1.4 1.4 BASMI 2;0 (1;3) 1.0 (0;2) 1.0 (0;2) 1.0 (0;2) 1.0 (0;3) 0 (-3;2) -1.0 (-4;2) 0 (-3;2) -1.0 (-4;2) 0.4 0.6 Pain 7.0 (5.6;8.1) 0.8*** (0.3;1.2) 2.9 (1.3;5.5) 0.7** (0.3;2.6) 3.3 (1.1;6.3) -2.6** (-8.8;1.9) -5.6 (-8.6;-1.1) -1.8*** (-6.8;1.9) -5.6 (-8.8;-1.1) 2.7 1.8 Pt. global 7.5 (6.4;8.4) 1.0*** (0.4;1.9) 3.0 (1.3;6.7) 0.6*** (0.2;2.1) 4.4 (2.3;6.9) -3.4*** (-6.5;0.8) -6.7 (-8.8;-1.1) -2.8*** (-6.3;0.8) -6.5 (-8.8;-1.1) 3.3 1.8 CRP (mg/l) 7.7 (0.9;22) 0.3* (0.3;2.2) 1.3 (0.3;8.5) 0.3** (0.3;2.5) 1.0 (0.3;5) -1.7 (-39.6;6.9) -5.2 (-79.7;19) -1.7 (-39.6;6.9) -5.2 (-79.7;19) 0.5 0.6 SPARCC MRI SIJ inflammation 14 (4;24.5) 4.0 (0;6.5) 2.0 (0;7.8) 2.0 (0;4.3) 2.0 (1;6) -5.5 (-30;2) -12.5 (-36;0) -5.5 (-30;2) -12.5 (-36;0) 0.9 1.1 SPARCC MRI spine infl. 8 (4;15) 0 (0;3.5) 1.0 (0;4.3) 0(0;2) 1.0 (0;3) -2.5** (-98;2) -8 (-55;0) -2.5* (-98;2) -8 (-55;0) 0.5 0.7 Median (IQR). Mann-Whitney test. * p&lt;0.05. ** p&lt;0.01. *** p&lt;0.001. Standardized response mean (SRM) and effect size (ES) ≥0.50 to &lt;0.80 and ≥0.80 represents moderate and high responsiveness. Conclusion ASAS HI showed good construct validity and responsiveness. References [1]Kiltz U. ARD 2015;74:830 [2]Kiltz U. ARD 2018;77:1311 [3]Krabbe. Rheumatology 2020;59:3358 [4]Walsh. ACR 2020 doi: 10.1002/acr.24482 [5]Molto. ARD 2021;80(11):1436 Disclosure of Interests Susanne Juhl Pedersen Speakers bureau: MSD, Pfizer, AbbVie, Novartis and UCB. Grant/research support from: AbbVie, MSD, and Novartis., Inge Juul Sørensen: None declared, Bente Jensen: None declared, Ole Madsen: None declared, Mette Klarlund: None declared, Jakob Møllenbach Møller: None declared, Mats Peter Johansson: None declared, Kasper K Gosvig: None declared, Mikkel Østergaard Speakers bureau: Abbvie, BMS, Celgene, Eli-Lilly, Galapagos, Gilead, Janssen, Merck, Novartis, Orion, Pfizer, Roche and UCB., Consultant of: Abbvie, BMS, Boehringer-Ingelheim, Celgene, Eli-Lilly, Hospira, Janssen, Merck, Novartis, Novo, Orion, Pfizer, Regeneron, Roche, Sandoz, Sanofi and UCB., Grant/research support from: Abbvie, Amgen, BMS, Merck, Celgene and Novartis.